Process for producing cards

ABSTRACT

A process for producing cards is provided, which can avoid exposure, on card surface, of unevennesses of components such as IC chips, capacitors and antenna coils mounted or formed on a mount substrate. This process comprises the steps of continuously feeding a mount substrate and simultaneously feeding a pair of sheet members on both surface sides of the mount substrate in such a manner that the mount substrate is interposed between the pair of sheet members; feeding an adhesive in fluid condition between each of the surfaces of the mount substrate and the sheet member opposite thereto; and regulating a distance between the pair of sheet members into a constant spacing and hardening the adhesive.

TECHNICAL FIELD

The present invention relates generally to a process for producing IC(integrated circuit) cards. More particularly, the present inventionrelates to a process for producing cards, which can avoid exposure, onthe card surface, of unevennesses of components such as IC chips,capacitors and antenna coils mounted or formed on a mount substrate.

BACKGROUND ART

In conformity with the rapid progress of electronic applicationtechnology, thin high-performance IC cards with large storage capacityare now increasingly employed for instantaneously carrying out inputsand outputs for information storage and processing with external memoryunits in the field of personal recognition, management of bank deposits,examination of railway tickets, supervision at expressway tollbooths,etc. Among various IC cards, especially, noncontact-type IC cards enableperforming information inputs and outputs through wave transmission andreception even at a given distance without the need to carry outtime-consuming operation, such as card insertion in a reader installedon an external processor side, for information input and output asdifferent from conventional contac-type IC cards. Therefore, contactlesstype IC cards are now becoming mainstream because of excellent operationefficiency, accuracy in information input and output and extremely highinformation processing speed.

Common IC cards are obtained by first overlaying one surface of asubstrate of a synthetic resin film such as a film of polyethyleneterephthalate with circuits with the use of a copper foil, a silverpaste or the like, subsequently superimposing IC chips, capacitors,antenna coils, etc. on the circuits, and covering the circuit side ofthe substrate with a laminate film having on its one side a heatsensitive or pressure sensitive adhesive layer.

However, these IC cards have a drawback in that unevennesses ofcomponents such as IC chips and capacitors are exposed on the laminatefilm.

Thus, IC cards of the following structure intended to minimize componentunevennesses on the cards have been developed.

The IC cards 120, as shown in FIG. 6, fundamentally, comprise a mountsubstrate 12 of a synthetic resin film 100 such as a film ofpolyethylene terephthalate, and transmission/reception coils 102 fortransmitting and receiving input/output wave signals and capacitors 104on the surface of the mount substrate 12. The mount substrate 12 hasdevice holes 114 wherein integrated circuits (IC chips) 106, such assemiconductor memory, for information storage and processing are fitted.Copper foil circuits 108 for wiring provided to form circuits betweencomponents are stuck to the mount substrate 12 through an adhesive layer112. Both surface sides of the mount substrate 12 are overlaid, by hotlaminating, with laminate films 110 having a thermal adhesive layer 109.

However, with respect to the IC cards of this structure, there stillremains the problem that unevennesses of components such astransmission/reception coils 102, capacitors 104, IC chips 106 andcopper foil circuits 108 for wiring are exposed on the surfaces of thelaminate films 110. Therefore, in the event of printing a company nameor other information on a card surface, it is difficult to useconventional printers. Special printers such as an ink jet printer mustbe employed.

Further, in the event that unevennesses of, for example, IC chips areexposed on IC card surfaces, there is such a danger that IC chips andother components are damaged by impact on the unevennesses when the ICcards are placed in a bag or the like and carried. As a result, readingof read information cannot be performed.

Still further, it is needed to disenable recognition of the presence ofcomponents such as IC chips in the IC cards for the purpose ofprohibiting alteration of information stored in the IC cards.

SUMMARY OF THE INVENTION

In these circumstances, it is an object of the present invention toprovide a process for producing cards, which can avoid exposure, on cardsurface, of ,unevennesses of components such as IC chips, capacitors andantenna coils mounted or formed on a mount substrate.

The present invention has been made with a view toward attainment of theabove problems and object. The process for producing cards according tothe present invention comprises the steps of:

continuously feeding a mount substrate and simultaneously feeding a pairof sheet members on both surface sides of the mount substrate in such amanner that the mount substrate is interposed between the pair of sheetmembers;

feeding an adhesive in fluid condition between each of the surfaces ofthe mount substrate and the sheet member opposite thereto; and

regulating a distance between the pair of sheet members into a constantspacing and hardening the adhesive.

By virtue of this process, the unevennesses of components, such as ICchips, capacitors and antenna coils, mounted or formed on a mountsubstrate are absorbed by the adhesive in fluid condition, and theirexposure on the card surfaces can be avoided.

Therefore, a company name or other information can be printed on a cardsurface by the use of conventional printers without the need to employspecial printers such as an ink jet printer. Further, even when the ICcards are placed in a bag or the like and carried, no impact would beexerted on components such as IC chips. Thus, the components areprotected, and damaging of the IC cards can be avoided. Still further,the presence of components such as IC chips in the IC cards cannot berecognized from outside, so that alteration of information stored in theIC cards can be prevented.

In the process for producing cards according to the present invention,one of the pair of sheet members preferably consists of a release sheet.

As a result, an adhesive layer can be exposed by stripping the releasesheet from the produced IC cards, and the IC cards can be stuck to, forexample, a surface of corrugated cardboard box through the exposedadhesive layer as contactless-type IC labels. Thus, the IC cards can beutilized in the information management for physical distribution systemand the like.

Moreover, with respect to the process for producing cards according tothe present invention, it is preferred that at least one of the pair ofsheet members consist of a release sheet, and that the process furthercomprise the steps of stripping the release sheet from the mountsubstrate after the hardening of the adhesive; and sticking a laminatesheet member onto adhesive layer surface exposed as a result of thestripping of the release sheet.

In this process, an adhesive layer can be formed on a surface of mountsubstrate in advance by the use of release sheet, and thereafter alaminate sheet member suitable for laminating can be stuck thereby tothe mount substrate.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a schematic diagram showing the first embodiment of theprocess for producing cards according to the present invention;

FIG. 2 is a schematic diagram showing a sheet spacing regulator for usein the process for producing cards according to the present invention;

FIG. 3 is a partial enlarged sectional view of an IC card obtained bythe first embodiment of the process for producing cards according to thepresent invention;

FIG. 4 is a partial enlarged sectional view of an IC card obtained byanother embodiment of the process for producing cards according to thepresent invention;

FIG. 5 is a schematic diagram showing the second embodiment of theprocess for producing cards according to the present invention; and

FIG. 6 is a partial enlarged sectional view of conventional IC card.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention will now be described withreference to the appended drawings.

FIG. 1 is a schematic diagram showing the first embodiment of theprocess for producing cards according to the present invention.

Referring to FIG. 1, numeral 10 generally denotes an apparatus forproducing cards of the present invention (hereinafter referred to simplyas “cards”).

A mount substrate 12 on which the same IC chips, capacitors, antennacoils, circuits, etc. are formed or superimposed, as in the conventionalstructure of FIG. 6, is fed from a delivery roll 14 via a guide roll 13.

A pair of sheet member supply rolls 16, 18 are provided on both rightand left surface sides of the mount substrate 12. Sheet members 20, 22are respectively fed from the sheet member supply rolls 16, 18 via apair of guide rolls 24, 26.

Sheets of synthetic resins such as polyethylene terephthalate andpolycarbonate are preferably used as the sheet members 20, 22. From theviewpoint of printability and prohibition of recognition of componentssuch as IC chips, it is preferred that the sheet members 20, 22 becomposed of, for example, a white or otherwise colored resin. It is alsopreferred that the thickness thereof should be in the range of 30 to 200μm. The sheet members 20, 22 are not limited to the above syntheticresin sheet, and can naturally be composed of papers such as animpregnated paper and a synthetic paper. Furthermore, the latermentioned release sheets (obtained by coating one surface side of, forexample, a synthetic resin sheet or an impregnated paper with a releasetreatment agent such as a silicone resin).

The feeding speed of the sheet members 20, 22 from the sheet membersupply rolls 16, 18 is synchronized with the feeding speed of the mountsubstrate 12 from the mount substrate delivery roll 14. The feedingspeed is set for, for example, 5 to 20 m/min.

Further, an adhesive 28, 30 in fluid condition is fed over respectivesurfaces 20A, 22A of the sheet members 20, 22 delivered from the sheetmember supply rolls 16, 18 through adhesive supply means 32, 35 such asdie coaters or T-dies.

After the application of the adhesive 28, 30 in fluid condition over therespective surfaces 20A, 22A of the sheet members 20, 22, the sheetmembers 20, 22 are guided by means of the pair of guide rolls 24, 26 sothat he mount substrate 12 is interposed between the sheet members 20,22 and so that the spaces defined by both surface sides of the mountsubstrate 12 and the sheet members 20, 22 are filled with the adhesive28, 30.

Although the adhesive in fluid condition for use is not particularlylimited as long as the adhesive has fluidity before hardening but, afterhardening, exhibits adherence and stickiness. Hot melt adhesivescomposed of, for example, a polyolefin resin (such as polyethylene resinor polypropylene resin), a polyester resin and a vinyl acetate resin;and adhesives hardenable by ionizing radiation such as ultraviolet lightor electron beams, composed of, for example, a urethane acrylate resinand a polyester acrylate resin can be preferably used.

In the embodiment of FIG. 1, a hot melt adhesive is employed as theadhesive 28, 30.

The feeding rate of adhesive 28, 30 is controlled in conformity with thedesired thickness and sheet feed speed. The gap between the guide rolls24, 26, although not particularly limited, ranges from millimeters tocentimeters, preferably, for example, 5 mm to 5 cm.

After the spaces defined by both surface sides of the mount substrate 12and the sheet members 20, 22 are filled with the adhesive 28, 30, themount substrate 12 overlaid through the adhesive 28, 30 with the sheetmembers 20, 22 is passed through a sheet spacing regulator 33 so thatthe distance between the sheet members 20, 22 is regulated into aconstant spacing. This constant spacing attained by the regulation,although depending on the card thickness, is preferably set so thatunevennesses of components such as IC chips can be absorbed and sealedby theadhesive 28, 30.

In this embodiment, the sheet spacing regulator 33 comprises three pairsof regulation rolls, each pair consisting of regulation rolls 34, 36disposed right and left with a gap, arranged so that the gaps aregradually regulated into the constant spacing. Although three pairs ofregulation rolls are employed in this embodiment, the sheet spacingregulator 33 can naturally consist of a pair of regulation rolls, twopairs of regulation rolls, or more pairs of regulation rolls. Further,although pairs of regulation rolls 34, 36 disposed right and left areemployed in this embodiment, as shown in FIG. 2, the sheet spacingregulator 33 can instead consist of a pair of regulation plates 38, 40whose gap is gradually regulated into the constant spacing.

In the use of a hot melt adhesive, the adhesive supply means 32, 35through the sheet spacing regulator 33 must be warmed in order tomaintain the fluid condition.

After the regulation of the distance between the sheet members 20, 22into the constant spacing, the mount substrate 12 overlaid through theadhesive 28, 30 with the sheet members 20, 22 is passed through a firstcooler 44 and a second cooler 48 so that the adhesive 28, 30 ishardened.

Although coolers of the air cooling or water cooling system can be usedas the coolers 44, 48, the use thereof can be avoided in the event thatnatural cooling is satisfactory.

Thereafter, the mount substrate 12 overlaid through the adhesive 28, 30with the sheet members 20, 22 is subjected to punching into IC cardconfiguration by means of a card punching device 67 to thereby obtain ICcards 69 as a final product. The rest after the punching is wound rounda take-up roll 65.

As a result, IC cards 1 as shown in. FIG. 3 are obtained (like numeralsare employed for like constituent members through the IC cards of thepresent invention and the conventional IC cards, this being truehereinafter).

In this embodiment, as shown in FIG. 4, one of the pair of sheet members20, 22 (sheet member 20 in FIG. 4) can be composed of a release sheet.In this instance, after the card is formed, an adhesive layer can beexposed by stripping the release sheet from the produced IC cards, sothat the IC cards can be stuck to, for example, a surface of acorrugated cardboard box through the exposed adhesive layer as IClabels. Thus, the IC cards can be utilized in the information managementfor a physical distribution system and the like.

FIG. 5 is a schematic diagram showing the second embodiment of theprocess for producing cards according to the present invention.

The constitution thereof is fundamentally the same as that of the firstembodiment. Like reference numerals are employed for like constituentsthrough the first embodiment and the second embodiment, and repetitionof detailed explanation is avoided.

In this embodiment, release sheets 21, 23 as sheet members 20, 22 arerespectively fed from sheet member supply rolls 16, 18 via a pair ofguide rolls 24, 26.

The release sheets 21, 23 delivered from the sheet member supply rolls16, 18 have respective release-treated surfaces 21A, 23A. An adhesive influid condition 28, 30, such as an adhesive hardenable by ionizingradiation, for example, ultraviolet light, is fed over therelease-treated surfaces 21A, 23A through adhesive supply means 32, 35such as die coaters or T-dies.

The distance between the release sheets 21, 23 is regulated into aconstant spacing by a sheet spacing regulator 33. Thereafter, the mountsubstrate 12 overlaid through the adhesive 28, 30 with the releasesheets 21, 23 is passed through a first ultraviolet irradiator 42. Thus,the adhesive 28, 30 is irradiated with ultraviolet light with the resultthat the adhesive 28, 30 is preliminarily hardened into a semihardenedform. The mount substrate 12 overlaid through the adhesive 28, 30 withthe release sheets 21, 23 is cooled by means of a first cooler 44 so asto remove any reaction heat generated by the preliminary hardening.

Further, after the cooling by means of the first cooler 44, the mountsubstrate 12 overlaid through the adhesive 28, 30 with the releasesheets 21, 23 is passed through a second ultraviolet irradiator 46.Thus, the adhesive 28, 30 is irradiated with ultraviolet light with theresult that the adhesive 28, 30 is hardened. Thereafter, the mountsubstrate 12 overlaid through the adhesive 28, 30 with the releasesheets 21, 23 is cooled by means of a second cooler 48 so as to removeany reaction heat generated by the hardening.

The ultraviolet irradiation in two stages for hardening, as comparedwith that in one stage, is effective in preventing the waving, warpageand unevenness occurrence of adhesive layers and sheet members caused byreaction heat.

It is preferred that the ultraviolet intensity of the first ultravioletirradiator 42 should be so set that the adhesive 28, 30 is preliminarilyhardened into a semihardened form. On the other hand, the ultravioletintensity of the second ultraviolet irradiator 46 is preferably so setthat the adhesive 28, 30 is completely hardened.

When the reaction heat is slight depending on the type of adhesive, itis not necessary to provide coolers.

Although the adhesive 28, 30 is irradiated with ultraviolet in twostages in this embodiment, the ultraviolet irradiation can naturally beperformed in three or more stages, or a single stage.

In this embodiment, because the adhesive 28, 30 must be hardened throughthe release sheets 21, 23, the release sheets 21, 23 are preferablyselected from among films of transparent resins permeable forultraviolet, such as polyethylene terephthalate and polycarbonate.Although the thickness of the release sheet is not particularly limited,from the viewpoint of strength and dimensional stability, it ispreferred that the release sheet have a thickness of 20 to 150 μm.

After the hardening of adhesive 28, 30 and removal of hardening reactionheat, the release sheets 21, 23 stuck on both surface sides of the mountsubstrate 12 are stripped by means of a pair of stripping guide rolls51, 53 and wound round a pair of take-up rolls 50, 52. After the releasesheets 21, 23 are stripped off, laminate sheets 58, 60 are fed from apair of laminate sheet ember supply rolls 54, 56 to a gap between a pairof pressure bonding rolls 62, 64. As a result, the laminate sheets 58,60 are stuck to the mount substrate 12 by virtue of the adherence of theadhesive 28, 30.

In this embodiment, a variety of sheets including the same sheets as theabove sheet members 20, 22 can be used as the laminate sheets 58, 60.

After the sticking of the laminate sheets 58, 60, the mount substrate 12overlaid through the adhesive 28, 30 with the laminate sheets 58, 60 issubjected to punching into IC card configuration by means of a cardpunching device 67 to thereby obtain IC cards 69 as a final product. Therest after the punching is wound round a take-up roll 65.

As a result, IC cards 1 as shown in FIG. 3 are obtained.

In this second embodiment, the cards can be produced by sticking thelaminate sheets after the hardening of adhesive layers on both surfacesides of the mount substrate 12. Therefore, in this embodiment, laminatesheets which cannot be easily brought into direct contact with theadhesive in fluid condition or laminate sheets composed ofultraviolet-impermeable papers or colored films can be used.

In this embodiment as well, in the same manner as in the firstembodiment, a release sheet can be used as one of the laminate sheets58, 60, or either of the release sheets 21, 23 can be left unstrippedwithout performing lamination at one side. In such an instance, the sameIC cards as in FIG. 4 can be produced which can be stuck to, forexample, a surface of a corrugated cardboard box as IC labels. Thus, theIC cards can be utilized in information management for a physicaldistribution system and the like.

The above-described embodiments of the present invention, however, in noway limit the scope of the present invention. For example, although theabove embodiments relate to a vertically arranged system, the presentinvention can also be applied by a horizontally arranged system.Further, although the same adhesive resin was employed in the adhesive28, 30 in the above embodiments, different types of adhesive resins canbe applied therein. Still further, the cards are not limited to ICcards, and the present invention can be applied for card-shaped productsbased on mount substrates with uneven surfaces.

In the process for producing cards according to the present invention,the unevennesses of components, such as IC chips, capacitors and antennacoils, mounted or formed on a mount substrate are absorbed by theadhesive in fluid condition, and their exposure on the card surfaces canbe avoided.

Therefore, a company name or other information can be printed on a cardsurface by the use of conventional printers without the need to employspecial printers such as an ink jet printer. Further, even when the ICcards are placed in a bag or the like-and carried, no impact would beexerted on components such as IC chips. Thus, the components areprotected, and damaging of the IC cards can be avoided. Still further,the presence of components such as IC chips in the IC cards cannot berecognized from outside, so that alteration of information stored in theIC cards can be prevented.

What is claimed is:
 1. A process for producing IC cards, comprising thesteps of: continuously feeding a mount substrate having unevenness ofcomponents on the surface thereof and simultaneously feeding a pair ofsheet members on both surface sides of the mount substrate in such amanner that the mount substrate is interposed between the pair of sheetmembers; feeding an adhesive in fluid condition on the surface of thesheet members; and regulating a distance between the pair of sheetmembers into a constant spacing and hardening the adhesive byinterposing the mount substrate between the surfaces of the sheetmembers on which the adhesive is fed, wherein the distance between thesheet members is narrowed gradually.
 2. A process for producing ICcards, comprising the steps of: continuously feeding a mount substrateand simultaneously feeding a pair of sheet members on both surface sidesof the mount substrate in such a manner that the mount subs isinterposed between the pair of sheet members; feeding an adhesive influid condition on the surface of the sheet members; and regulating adistance between the pair of sheet members into a constant spacing andhardening the adhesive by interposing the mount substrate between thesurfaces of the sheet members on which the adhesive is fed, wherein oneof the pair of sheet members consists of a release sheet.
 3. A processfor producing IC cards, comprising the steps of: continuously feeding amount substrate and simultaneously feeding a pair of sheet members onboth surface sides of the mount substrate in such a manner that themount substrate is interposed between the pair of sheet members, whereinat least one of the pair of sheet members consists of a release sheet;feeding an adhesive in fluid condition on the surface of the sheetmembers; regulating a distance between the pair of sheet members into aconstant spacing and hardening the adhesive by interposing the mountsubstrate between the surfaces of the sheet members on which theadhesive is fed; stripping the release sheet from the mount substrateafter the hardening of the adhesive; and sticking a laminate sheetmember onto adhesive layer surface exposed as a result of the strippingof the release sheet.